For example, in the case of using multiple gases as with a semiconductor process, a flow rate controller is provided for each gas line in order to control a flow rate of each of the gases. In addition, a reduction in size of such a flow rate controller is increasingly demanded, and therefore a method that supplies power from a power supply apparatus, which is adapted to comprehensively manage respective flow rate controllers, via a communication cable without incorporating a power source device in any of the flow rate controllers is also used.
Meanwhile, in general, at the time of start-up, inrush current larger than current at the time of normal operation flows through a power supply line, and therefore it is necessary to equip a power supply apparatus with a power source device having sufficiently large current capacity.
However, as the number of flow rate controllers is increased, overall inrush current also increases correspondingly, and consequently the size of a power source device is increases. Also, for example, in a semiconductor process system, a reduction in size of a power supply apparatus may also be required. However, an increase in size of a power source of the power supply apparatus may give rise to the problem of being unable to fulfill the requirement.